Ecology of Mined WV Watersheds: Monongahela River to Tug Fork

J. Todd Petty, PhDDivision of Forestry & Natural Resources

Surface Mine Drainage Task Force – Morgantown, WVMarch 31, 2010

Acknowledgements

Watershed processes in intensively mined landscapes.•Monongahela River•Pigeon Creek

Aquatic ecosystem functions on reclaimed surface mines.•Samples•Hobet•Argus

KEY TOPICS1. Dominant stressor identification;2. Landscape indicators of instream condition;3. Interactions among stressors;4. Threshold responses (local and regional scale)

Functional value of habitat enhancement structures as mitigation for mining related impacts•L. Coal River

WVU / WVWRI Research Areas

Landscape ThresholdsA level of activity on the landscape (e.g., mining, development, agriculture) that results in an unacceptable shift from functional to impaired conditions.

Non-linear change point thresholds.• Abrupt change in community structure

Linear functional thresholds.• Cross-over to “impaired” conditions

• Loss of a smallmouth bass fishery

• WVSCI < 68

• Mining Intensity• Coal Geology (freeport,

kittanning, pittsburgh)• AMD Chemistry• Flow• Temperature• Habitat Quality• Invertebrates• Fishes• OM decomposition

Petty, J. T., Fulton, J. B., Merovich, G. T, Jr., Strager, M. P., Stiles, J., and Ziemkiewicz, P. F. IN REVIEW. Landscape indicators and thresholds of ecological impairment in an intensively mined Appalachian watershed. Journal of the North American Benthological Society.

Mining Thresholds - Northern CoalfieldsKittanning

Freeport

Bayesian Change Point Analysis

5% mining – loss of HQ conditions18% mining –change to “impaired” conditions.

Validated at an 85-95% correct classification rate.

100

68

40

Mon Basin Conclusions• There are identifiable mining

thresholds that produce downstream responses.

– 5% mining – shift from high quality to good conditions.

– 18% mining – shift from fair conditions to impaired.

• Thresholds vary depending on coal geology.

– Freeport coal geology has lowest “functional” thresholds.

• Validated models provide the baseline conditions needed for making management decisions (restoration and permitting).

Coal Geology Mining Intensity Residences

Southern WV Coalfields:

1. Variable coal geology, mining intensity, and population density.

2. People live in the floodplains and wastewater services are “spotty.”

3. Need for technical support for permitting decisions (thresholds, stressor interactions, visual decision support technologies).

Pigeon Creek Watershed

• 41 sites• Mining Intensity• Residential Development• Independent and

Interactive effects• Effects on wq, hq, and

inverts• Mining thresholds• Off-site mitigation

opportunities• Directing restoration and

mitigation towards dominant limiting stressors

Merriam, E., G. T. Merovich, and J. T. Petty. IN REVIEW. Additive effects of mining and residential development on stream conditions in an intensively mined Appalachian watershed. Journal of the NA Benthological Society

Parcel Density (#/km2)

0 20 40 60 80 100

Tot

al M

inin

g (%

)

0

20

40

60

80

MinedDevelopedCombined SmallCombined LargeReference

Pigeon Creek Design

•Site independence•Sampling across mining and development gradient.

Correlation with % MiningVariable r pWater Quality

Alkalinity* 0.74 0.004

Acidity* -0.83 <0.001Conductivity* 0.91 <0.0001

Ba* 0.68 0.010

Ca* 0.84 <0.001Mg* 0.81 <0.001

Na* 0.79 0.002

SO4* 0.89 <0.0001WQ PC1 0.90 <0.0001

Macroinvertebrate MetricsmWVSCI -0.64 0.019

EPT Richness -0.58 0.036

E Richness -0.56 0.047%E excluding Baetidae -0.57 0.041

%Dominant 0.58 0.036

• Increased WQ PC1, conductivity and associated dissolved parameters

• Decreased sensitive taxa (esp. Mayflies)

• No effect on habitat quality or complexity

Variable r pPhysical HabiatCV Depth -0.81 0.004LWD/m -0.66 0.037Retentiveness -0.65 0.044%Canopy Cover -0.65 0.042

Water QualityAlkalinity* 0.78 0.008Acidity* -0.73 0.017Conductivity* 0.69 0.023NO2* 0.63 0.049WQ PC1 0.70 0.024

Macroinvertebrate MetricsmWVSCI -0.73 0.017Total Richness -0.69 0.027EPT Richness -0.74 0.015E Richness -0.72 0.019Total Abundance 0.71 0.020%EPT excluding Baetidae -0.93 <0.001%E excluding Baetidae -0.85 0.002%Tolerant 0.64 0.046%Dominant 0.75 0.012%Chironomidae 0.65 0.043

• Decreased habitat complexity

• Increased conductivity and WQ PC1

• Decreased sensitive taxa and increased tolerant taxa

Correlation with Development

Additive Effects of Mining and Residential Development

asin % Mining

0.0 0.2 0.4 0.6 0.8 1.0 1.2

log

EP

T R

ichn

ess

0.6

0.8

1.0

1.2

1.4

1.6

Mined SitesDeveloped SitesCombined SitesReference SitesMined RegressionCombined Regression

log Parcel Density (#/sq km)

0.8 1.0 1.2 1.4 1.6 1.8 2.0D

evia

tion

from

Min

ing

Reg

ress

ion

-0.2

-0.1

0.0

0.1

0.2

0.3

0.4

0.5

R2=0.22; p=0.080

• Mining has a measurable negative impact.• Worst conditions observed when both stressors are present.• The degree of additional impact is proportional to the level of

development intensity (i.e., additive).

Mining only

Mining + Development

Impairment Thresholds: Pigeon Creek

0 20 40 60 80

02

46

81

01

2

Parcel Density (#/sq km)

%E

(ex

clud

ing

Bae

tidae

)

0.2

0.4

0.6

0.8

Pro

babi

lity

of a

Cha

nge

Poi

nt

0 20 40 60

24

68

10

12

14

Total %Mining

E R

ichn

ess

0.0

50

.10

0.1

50

.20

0.2

50

.30

0.3

5

Pro

babi

lity

of a

Cha

nge

Poi

nt

Bayesian Change Point Analysis

5% mining –loss of HQ conditions28% mining – change to “impaired” conditions5 parcels / km2 – loss of HQ conditions15 parcels / km2 – change to “impaired” conditions

Parcel Density (#/km2)

0 10 20 30 40 50 60

Tot

al %

Min

ing

0

10

20

30

40

50

60

100%

37%

7%

Impairment Thresholds: Pigeon Creek“Functional” Thresholds

The likelihood that mining will produce a downstream impairment depends on the amount of residential development in the watershed.

Definitely Impaired

Probably Impaired

93% streams

“impaired”

0% streams

“impaired”

63% streams

“impaired”

The Pigeon Creek mainstem is a train wreck.

How much of the impairment can be attributed to mining?

To what extent could the conditions be improved through reduced non-mining stressors?

Can the watershed withstand any additional mining?

Current ConditionIdeal Future Condition

- 100% dev / + 0% mining

Alt Future Condition 3- 50% dev / + 0% mining

Alt Future Condition 4- 50% dev / + 10% mining

Pigeon Futures

Green =

Probably not

impaired

Yellow =

Probably impaired

Red =

Definitely impaired

100,0

50,0

100,10

50,10

10,0

10,10

0,00,10100,50

Ideal Condition

Consensus?

Unacceptable

First # = % reduction in development related stressSecond # = % increase in mining related stressFunctional Stream Length = streams classified as “green”

Pigeon Creek Alternative Futures

Pigeon Creek ConclusionsoSimply avoiding future mining

impacts does not help in dealing with existing degradation.

oAFA allows us to visualize a range of future conditions and reach consensus on an acceptable future endpoint to manage towards.

oAFA and management of multiple stressors is untenable at the stream segment scale. But…

oEffective management of actively developing watersheds is possible at the 10-digit HUC scale.

Pigeon CreekMingo County, WV

Final ThoughtsoThe MTM/VF conflict must be resolved (laws demand that

mining occur and that water resources be protected).

oA resolution does not exist at the stream scale, but does exist at the watershed scale (12-digit and 10-digit HUC).

oA resolution will require:

oAllowing localized impacts (development of all types produces localized impacts).

oPlacing limits on the total amount of mining allowed at the 12- or 10-digit HUC scale (needed to meet state narrative standards).

oA regulatory process that enables (facilitates) innovative mitigation (channel restoration, wastewater treatment, etc.)

Coal Geology Mining Intensity Residences

Need for:

1. Predictive models linking instream conditions to landscape attributes across the full range of coal geology, mining intensity, and residential development.

2. Alternative Futures Analysis for the region.

3. Development of watershed specific management plans for the MTR/VF region.

Red watersheds are probably impaired at the outflow.

Orange watersheds are highly vulnerable to additional mining impact.

Map must be refined and then used to make permitting decisions.